Mobile version

Waves across the water

Image of the Month - February 2000

Longitude-time diagram showing Rossby waves in the Indian Ocean at 29°S latitude. (Credits Legos)

Like a stone skimming across the water creates ripples on the surface, perturbations in the oceans form waves that propagate. These waves may be small-scale ripples formed by the wind or large-scale planetary waves, which we call Kelvin or Rossby waves depending on their origin and direction. Planetary waves transport heat and energy across the oceans. We can detect them using satellite altimetry data because they cause small variations in sea level (of the order of ten centimeters). They can be clearly seen by mapping the oceans at regular intervals or in longitude-time diagrams, where the phenomenon is even more striking. Longitude-time diagrams show sea level variations over time along an east-west axis, at a given latitude. Ocean waves appear in these diagrams as a series of straight lines.

Websites on this subject:

EnglishFrançaisEspañol
Rss feedsContactSitemapPartnersFAQGlossaryLexiconMobile
You must enable cookies in your browser preferences to save the modifications
You are using an older version of Internet Explorer, please update to take full advantage of Aviso+ features

Customize the home page

View all widgets
Reduce display
Public profile
User profile

Select/Deselect widgets

Discover AVISO+

Customizable home, reading tools, products search guide, etc.. Discover step by step the features of the new site AVISO+.

Customizable homepage

The new home page is composed of blocks called "widgets".

Rearrange the blocks with a "Click & Drop".

Hide a widget with the cross at the top right. Reset or add a widget with the "wrench" icon. The "User" and "Public" profiles offer a predefined organization.

All the modifications are automatically saved as cookies on your machine so as to enable you to have your own specific AVISO+.

Reading tools

Ease your reading by choosing the page background colour (black/white) and/or by modifying the font size.

Browsing menu and breadcrum trail

To ease your browsing through AVISO+, you can use at any time the main banner items with the interactive submenus or use the browsing menu on the left side of the screen (it is open by default). For more readiness of the page contents, you can fold and unfold the browsing menu by clicking on the tab. At any time you can know where you are thanks to the browsing menu or the breadcrum at the top of the page.

Products search guide

The first submenu of the "Data" banner item leads you to a new search form enabling you to find quickier the product that suits your needs. The list of results is updated according to your selection criteria.

AVISO+ Multimedia

The first submenu of the "Multimedia" banner item leads you to AVISO+ collections of images and videos linked to altimetry and its applications. Have a nice visit!